Carina Bend Environmental Water Management Plan · 7. Fallen woody debris provides feeding sites...

Carina Bend Environmental Water Management Plan

Carina Bend Environmental

Water Management Plan


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Document Control

Version

Number

Description

Issued To

Issue Date

1. Draft for project team review

M. Cooling

30/3/2016

2. Draft for Mallee CMA review

E. Healy

7/04/16

3. Final Draft

E. Healy

27/04/16

4. Reviewed and updated J. Munro Mar 2020

Citation

Please cite this document as:

Riverness and Ecological Associates (2016) Carina Bend Environmental Water Management Plan,

Report prepared for Mallee CMA, Mildura Victoria

Contact

For queries regarding this document, please contact:

James Kellerman

[email protected]

General Manager

Mallee Catchment Management Authority

This publication may be of assistance to you but the Mallee Catchment Management Authority and

its employees do no guarantee that the publication is without flaw of any kind or is wholly appropriate

for your particular purpose and therefore disclaims all liability for any error, loss or other

consequence that may arise from you relying on any information in this publication.


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Table of contents

DOCUMENT CONTROL ........................................................................................................................ 2

TABLE OF CONTENTS ......................................................................................................................... 3

EXECUTIVE SUMMARY ....................................................................................................................... 5

1 INTRODUCTION ............................................................................................................................. 6

2 SITE OVERVIEW ............................................................................................................................ 6

2.1 Site location ........................................................................................................................................... 6

2.2 Catchment setting.................................................................................................................................. 7

2.4 Carina Bend .......................................................................................................................................... 8

2.5 Conceptualisation of the site ................................................................................................................. 9

2.7 Land status and management .............................................................................................................. 12

2.9 Wetland characteristics ........................................................................................................................ 14

2.10 Management scale ............................................................................................................................... 15

2.12 Environmental water sources ............................................................................................................... 17

2.13 Related agreements, policy, plans and activities .................................................................................. 17

3 HYDROLOGY AND SYSTEM OPERATIONS ............................................................................. 19

3.1 Wetland hydrology ............................................................................................................................... 19

4 WATER DEPENDENT VALUES .................................................................................................. 22

4.1 Environmental values ........................................................................................................................... 22

4.2 Social values ........................................................................................................................................ 32

4.3 Recreation ............................................................................................................................................ 33

4.4 Economic values .................................................................................................................................. 33

4.5 Significance .......................................................................................................................................... 33

5 ECOLOGICAL CONDITION AND THREATS .............................................................................. 34

5.1 Current condition .................................................................................................................................. 34

5.2 Water related threats ............................................................................................................................ 35

6 MANAGEMENT OBJECTIVES .................................................................................................... 38

6.1 Management goal ................................................................................................................................ 38

6.2 Ecological objectives ............................................................................................................................ 38

6.3 Hydrological objectives ........................................................................................................................ 39

6.4 Watering regime ................................................................................................................................... 40

7 MANAGING RISKS TO ACHIEVING OBJECTIVES ................................................................... 42

8 ENVIRONMENTAL WATER DELIVERY INFRASTRUCTURE ................................................... 44

8.1 Constraints ........................................................................................................................................... 44

8.2 Infrastructure or complementary works recommendations ................................................................... 45

9 DEMONSTRATING OUTCOMES................................................................................................. 46

9.1 Monitoring priorities at the site ............................................................................................................. 46

10 CONSULTATION ...................................................................................................................... 47

11 KNOWLEDGE GAPS AND RECOMMENDATIONS ................................................................ 48

REFERENCES ..................................................................................................................................... 49


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ABBREVIATIONS AND ACRONYMS ................................................................................................. 51

APPENDIX 1 – FAUNA SPECIES LIST .............................................................................................. 52

APPENDIX 2 – ECOLOGICAL VEGETATION CLASSES ................................................................. 54

APPENDIX 3 – FLORA SPECIES LIST .............................................................................................. 56


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Executive summary

Environmental Water Management Plans (EWMPs) have been developed for key sites in the Mallee

region. The Mallee Waterway Strategy 2014-22 (Mallee CMA, 2014) identified 23 Waterway

Management Units (WMU) from 216 targeted waterways in the Mallee. The interconnectedness and

commonality of threats impacting on the waterway values were used to group the WMUs into

planning units. This EWMP has been developed for the Carina Bend WMU sub-unit, hereafter

referred to as Carina Bend. The EWMP will help to guide future environmental watering activities for

this area.

The Carina Bend FMU features a lagoon system nearly 5km in length (Carina Bend Wetland) as well

as two smaller, unnamed wetlands and low meander scroll complexes supporting River Red Gum

woodland vegetation communities. The central floodplain supports higher terraces with Black Box

and lignum vegetation communities.

Carina Bend supports species of high conservation significance including Regent Parrot, Brown

Tree-creeper and White-browed Tree-creeper and Carpet Python. These species rely on the health

of large mature River Red Gums, which are prevalent with the target area. The wetland potentially

provides excellent seasonal habitat for fish, frogs and waterfowl.

The management goal for Carina Bend is “To provide a water regime that will support the health of

fringing mature River Red Gum and provide seasonal habitat for native fish, frogs and waterfowl.”

The ecological objectives to support the management goal for Carina Bend are:

• Support the health of mature River Red Gum trees along the wetland perimeter

• Provide seasonal aquatic habitat that supports a diverse population of native fish and

frogs

• Reliable nesting and feeding habitat for waterfowl in winter and spring

• Diverse macrophyte and frog population supported by healthy Lignum Swampy

Woodland vegetation

The optimal watering regime is to maintain Carina Bend Wetland as a semi-permanent freshwater

wetland, with a seasonally inundated fringe.

Fill Carina Bend Wetland every second year in late winter/early spring to 46m AHD, with water levels

falling naturally by seepage and evaporation over summer and autumn. In every fourth year, fill

wetland to 46.7m AHD to inundate the Lignum communities in September, with water levels falling

naturally by seepage and evaporation over summer and autumn.

There is currently no infrastructure in place to manage watering of the target area.

Recommendations that will significantly enhance the area able to be inundated with environmental

water have been made.


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1 Introduction

This Environmental Water Management Plan (EWMP) has been prepared by the Mallee Catchment

Management Authority (CMA) to establish the long-term management goals of Carina Bend.

The key purposes of the EWMP are to:

• identify long-term objectives and water requirements for the wetlands, which have

been identified as a priority by the Mallee CMA;

• provide a vehicle for community consultation, including for the long-term objectives

and water requirements of the wetlands;

• inform the development of seasonal watering proposals and seasonal watering

plans; and

• inform the long-term watering plans to be developed under the Basin Plan

requirements.

2 Site overview

2.1 Site location

The Mallee CMA region is situated in the north-west of Victoria. The area of responsibility is close to

39,000 km2 (3.9 million ha) and has a regional population estimated to be 65,000. Population centres

include Mildura, Birchip, Sea Lake, Ouyen, Robinvale, Red Cliffs and Merbein.

The boundaries of the Mallee CMA region cover almost one fifth of Victoria, making it the largest

area managed by a CMA in the state.

Approximately 40% of the land area within the Mallee CMA boundary is public land, consisting mainly

of national parks, reserves, wilderness, and large areas of riverine and dryland forests. The other

60% is predominantly dryland crops, but there is also a significant investment in irrigated horticulture

including grapes, citrus, almonds, olives and vegetables along the Murray River corridor. Irrigated

crops contribute over 40% of the value of agricultural production for the region.

In 2006, the Mallee CMA engaged consultants (Ecological Associates, 2006) to investigate water

management options for the Murray River floodplain from Robinvale to Wallpolla Island. One of the

major outcomes of these investigations was the development of a system of Floodplain Management

Units (FMUs). These divide the floodplain into management units in which water regimes can be

managed independently, but which are relatively consistent in their ecological values and land uses.

The Mallee CMA has based its environmental water management plans on these FMUs to support

effective management of hydrologically connected systems. In addition to this, the Mallee CMA has

also used individual FMUs or groupings of FMUs to form Waterway Management Units (WMUs) for

planning within its Mallee Waterway Strategy.

The site for this plan is the Carina Bend FMU, hereafter referred to as Carina Bend in this document.

Carina Bend is located within the Happy Valley WMU, 25km south west of Robinvale on the Murray

River floodplain Figure 1.

A regional context document (North, 2014a) has been prepared to compliment the Mallee CMA

EWMPs and should be read in conjunction with this document.


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Figure 1 – Carina Bend

2.2 Catchment setting

Carina Bend is in the Robinvale Plains bioregion within the Mallee CMA region. The majority of the

bioregion is a narrow gorge confined by the cliffs along the Murray River. These are entrenched

within older up-faulted Cainozoic sedimentary rocks. Alluvium deposits from the Cainozoic period

gave rise to the red brown earths, cracking clays and texture contrast soils (Vertosols, Chromosols

and Sodosols). The floodplain supports Riverine Grassy Forest and Riverine Grassy Chenopod

Woodland ecosystems (DEPI, 2014).


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2.3 Carina Bend

Carina Bend is situated on the Murray River floodplain, 25km south west of Robinvale, between the

townships of Wemen and Happy Valley. The Carina Bend FMU features a lagoon system nearly 5km

in length (Carina Bend Wetland) as well as two smaller, unnamed wetlands and low meander scroll

complexes that support River Red Gum woodland vegetation communities. The central floodplain

supports higher terraces with Black Box and lignum vegetation communities (Ecological Associates,

2007c).

Until recently, wetlands that comprise the south western end of Carina Bend Wetland (from the entry

point at 1081.5 river km) have been used to hold irrigation water (Ecological Associates, 2007c).


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2.4 Conceptualisation of the site

Carina Bend is represented by a conceptual model which is a visual representation of the processes and components within the target area that are discussed

throughout this EWMP.

Carina Bend


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Carina Bend WMU sub-unit is located between 1081 and 1096 river kilometres. It is 25km south west of

Robinvale and 24km downstream of Euston weir.

1. The Carina Bend Wetland is comprised of a series of wetlands nearly 5km long that can join up during

high flows. The deepest points are approximately 3 metres.

2. Prior to river regulation parts of these wetlands would have been inundated annually during winter flows.

Water levels would have dropped over the summer and autumn exposing the wetland edges and

encouraging macrophyte growth.

3. Watering to support semi-permanent water in the channel will provide habitat for small bodied fish such

as Gudgeon species and reliable aquatic habitat for waterfowl.

4. Mature, hollow bearing River Red Gum line the wetlands and Murray River frontage. Watering Carina

Bend wetland will result in improved tree health for significant areas of River Red Gums along the

channel.

5. Hollows in mature River Red Gum provide important habitat for fauna including Regent Parrot and

Carpet Python which have been recorded breeding at the site.

6. The northern end of Carina Bend Wetland spreads out into areas of shallow water and sandy benches.

During and following inundation, the Lignum Swampy Woodland and Intermittent Swampy Woodland will

support a complex habitat structure of macrophyte beds, overhanging River Red Gum branches, shrubs

and lignum. These areas will provide excellent frog habitat.

7. Fallen woody debris provides feeding sites for the Brown Tree-creeper as they forage for insects from

the ground to the canopy. Appropriate inundation frequencies will support tree health and the long-term

supply of woody debris.

8. Carina Bend Wetland supports Floodway Pond Herbland in the channel fringed by Intermittent Swampy

Woodland.

9. Lignum Swampy Woodland, Lignum Swamp and Riverine Chenopod Woodland are present in adjacent,

higher areas of the floodplain. Other terraces, wetlands and channels also host areas of Shallow

Freshwater Marsh, Grassy Riverine Forest and Shrubby Riverine Woodland.

10. River regulation and water extraction for irrigation have reduced the frequency, duration and magnitude

of inundation of floodplain wetlands in this section of the Murray River.

11. The floodplain is currently only inundated during very high river flows. Reduced floodplain and wetland

inundation have contributed to reductions in the diversity and productivity of riparian and floodplain

vegetation communities and a reduction in habitat availability and structural complexity for aquatic and

terrestrial fauna. Channels and wetlands are lined with juvenile River Red Gums that germinated

following previous inundation events.

12. Some channels at the site have been modified and deepened for irrigation supply, reducing the width

and complexity of the littoral zone.


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2.6 Land status and management

Several agencies and individuals are involved in managing the land and water at Carina Bend (Table

1). Land management boundaries are shown in Figure 2.

Carina Bend is subject to three public land classifications: Murray River Park, Murray River Reserve

and Carina Bend Riverine Forest. Parks Victoria is the public land manager at Carina Bend. There is

also an area of private land within Carina Bend.

Table 1 - Stakeholders for the Carina Bend EWMP

Group

Role

Parks Victoria

Land Manager

Mallee CMA

Regional waterway and environmental management

Department of Environment, Land, Water and Planning

(DELWP)

State level environmental management planning,

land manager, threatened species manager

Victorian Environmental Water Holder (VEWH)

Manager of Victoria’s environmental water

entitlements

Robinvale Claimant Group

Tati Tati community representatives

Latji Latji community representatives

Indigenous representation

Wemen Progress Association

Local community representation


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Figure 2 - Land management boundaries within Carina Bend


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2.8 Wetland characteristics

A brief overview of the main characteristics of the wetlands at Carina Bend is provided in Table 2.

Wetland types found within Carina Bend are shown in Figure 3.

Table 2 - Wetland characteristics at Carina Bend

Characteristics Description

Name Carina Bend

Mapping ID

(Wetland Current layer)

Carina Bend Wetland: 12238

Unnamed wetland: 12170

Unnamed wetland: 12174

Area of wetlands in target area 93.6 ha

Bioregion Robinvale Plains

Conservation status

Bioregion conservation status: areas of EVCs listed as Vulnerable,

Depleted and Least Concern

Land status

Public land: Proposed Murray River Park, River Murray Reserve, Carina

Bend Riverine Forest/Crown land; private land

Land manager Parks Victoria, DELWP

Surrounding land use

Dryland cropping, irrigation agriculture (almonds, grapes and oranges),

town of Happy Valley

Water supply Natural inflows from the Murray River and local catchment runoff

Wetland category

(Wetland Current layer)

Carina Bend Wetland: Deep Marsh

Unnamed wetland #12170: Shallow Marsh

Unnamed wetland #12174: Deep Marsh

Wetland depth at capacity Carina Bend Wetland: approximately 3 m at the deepest points


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Figure 3 - Wetland types at Carina Bend

2.9 Management scale

The whole of Carina Bend has a water requirement as a floodplain complex, but the focus of this plan

is the area of the floodplain where environmental water can be managed, following the construction of

the infrastructure proposed in this plan. This target area consists of Carina Bend Wetland and an area

of Grassy Riverine Forest / Floodway Pond Herbland Complex and Intermittent Swampy Woodland.

The target area is 135.9 ha, as shown as the inundation extent at 46.7 m AHD in Figure 4.


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Unnamed wetlands #12174 and #12170 are excluded from the target area. Expansion of the target

area is possible only with significant alterations to Murray River operations such as large releases

from storage. This is beyond the scope of this plan but is being addressed at the Murray-Darling

Basin scale.

Figure 4 - Target area for the Carina Bend EWMP consisting of the areas of Carina Bend Wetland

inundated at a level of 46.7m (AHD).


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2.11 Environmental water sources

The Environmental Water Reserve (EWR) is the legally recognised amount of water set aside to meet

environmental needs. The EWR can include minimum river flows, unregulated flows and specific

environmental entitlements. Environmental entitlements can be called out of storage when needed

and delivered to wetlands or streams to protect their environmental values and health.

The Victorian Environmental Water Holder (VEWH) is responsible for holding and managing Victoria’s

environmental water entitlements.

Environmental water for the target area may be sourced from the water entitlements listed in Table 3

and further explained in the Regional Context Document (North, 2014a). Previous environmental

watering at Carina Bend is outlined in the Environmental Watering section of this EWMP.

Table 3 - Summary of environmental water sources available to Carina Bend

Water entitlement

Responsible agency

Murray River unregulated flows

Murray River surplus flows Murray-Darling Basin Authority

Victorian Murray River Flora and Fauna Bulk

Entitlement

Victorian Environmental Water Holder

Commonwealth water

Commonwealth Environmental Water Holder

Donated water

Victorian Environmental Water Holder

Source: (Commonwealth Department of the Environment, 2016; DELWP, 2016a)


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2.12 Related agreements, policy, plans and activities

There is a range of National and State Acts, policies and strategies that direct management of the

target area. Those with particular relevance to the site and the management of its environmental

values are listed in Table 4. For the functions and major elements of each refer to the Regional

Context Document (North, 2014b).

Table 4 - National and state legislation relevant to management of the target area

Jurisdiction Legislation, agreement or convention

National Environment Protection and Biodiversity Conservation Act 1999

State Flora and Fauna Guarantee Act 1988

State DELWP Advisory List of Threatened Vertebrate Fauna

The Carina Bend EWMP was first developed in 2012. This document is a full revision of the 2012

EWMP.

The Mallee Waterway Strategy (2014) identifies Carina Bend Wetland as a medium priority wetland in

the Mallee CMA region.

The Strategy identifies the need to review EWMPs across the WMU that includes Carina Bend

(Management Action F1.1). This updated Carina Bend EWMP contributes to this action.

A number of earlier investigations into the Murray River floodplain are relevant to Carina Bend and

have been considered in the development of this EWMP. These include salinity management plans,

flow studies, and an investigation into River Red Gum health by the Land Conservation Council (LCC,

1989) and the Victorian Environmental Assessment Council (VEAC, 2008).

Carina Bend was also one of the areas included in the Investigation of Water Management Options

for the Murray River – Robinvale to Wallpolla (Ecological Associates, 2007c).


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3 Hydrology and system operations

Wetland hydrology is the most important determinant in the establishment and maintenance of

wetland types and processes. It affects the chemical and physical aspects of the wetland which in turn

affects the type of flora and fauna that the wetland supports. A wetland’s hydrology is determined by

the physical form of the wetland, surface and groundwater inflows and outflows in addition to

precipitation and evapotranspiration. Duration, frequency and seasonality (timing) are the main

components of the hydrological regime for wetlands and rivers.

Hydrology at Carina Bend is best described using gauge #414203 (Murray River @ downstream of

Euston Weir).

3.1 Wetland hydrology

Murray River hydrology

Murray River hydrology has been altered significantly by regulation and diversion upstream. Storages

in Victoria and New South Wales are managed to capture water in winter and spring and to deliver

this water at manageable flow rates to consumers (primarily irrigators) during the summer. The impact

on river hydrology has been a reduction in large winter and spring flow peaks and enhancement of

low summer flows.

The ecologically significant effects of these hydrological changes have been to:

• largely eliminate flowing water habitat under normal regulated flows;

• reduce the frequency and duration of floods that reach higher-level wetlands and

floodplain areas.

The hydrology of the river at Carina Bend has been characterised by analysing the MSM_Bigmod

daily flow series for Natural and Current (Baseline scenarios, using data from 1891 to 2009 (Figure 5).

The river now spends more time fluctuating at very low flows, less than 10,000 ML/d, than under

natural conditions as indicated by higher than natural spell frequency but much shorter spell duration.

Events that inundate low-lying wetlands, up to 30,000 ML/d, now occur at 40% the frequency of

natural conditions. The duration of these events, when they do occur, has also been reduced by

almost 40%. The impact on floodplain inundation is also significant. While the duration of spells

exceeding 70,000 ML/d under current conditions is similar to natural, the frequency of these events

has declined to as much as 50% of natural. This has resulted in a major increase in the interval

between spells for very high flows.


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Figure 5. Spells analysis for River Murray flows upstream of Lock 11 (using data from Euston DS) for

Natural and Baseline scenarios over a 114-year modelled period (Gippel, 2014).

Mean annual flows at Euston have been reduced by 49 per cent from natural levels, although

seasonality of mean monthly flows is largely unaltered (Maheshwari, Walker and McMahon, 1993;

Ecological Associates, 2006) as shown in Figure 6.

Figure 6 - Distribution of median flows and 90th percentile flows for each month in the Murray River

through Euston Weir for pre-regulated and regulated (current) conditions (Ecological Associates, 2006).

Wetland hydrology and system operations

Water first enters the system at a former pump station at 1086 river km at flows of


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The wetland is effectively full when river levels reach 46.7 m AHD, which corresponds to a flow of

approximately 55,000 ML/d (Gippel 2008). Under pre-regulation condition Carina Bend wetland would

have filled on average 67.5 times in 100 years and post-regulation this has reduced by almost 50%.

The event duration has also reduced from 98 days by almost 50%.

Under pre-regulation conditions the wetland would have commenced to fill at flows of 25,000 ML/day

on average 97.4 times per 100 years compared with 70.2 times per 100 years post-regulation. The

median duration of inundation events has been reduced from 177 days to 100 days since river

regulation (Gippel, 2014).

Environmental watering

Environmental watering has been provided at Carina Bend wetland in 05-06, 09-10, 17-18, and 19-

20; details are presented in Table 5. The water was pumped onto the floodplain using temporary

earth banks and mobile pumps.

Table 5 - A summary of environmental watering at Carina Bend

Water year

Time of

inflow

Environmental Water

Source

Source

volume (ML)

Total volume

(ML)

Area (ha)

inundated

2005

Spring

Surplus flows EWA

340

128

468

80

2006

Autumn

Donated

695

695

100

09-10 Autumn-Winter EWR 1013 1013 74

10-11 Summer Natural flows n/a n/a n/a

16-17 Spring Natural flows n/a n/a n/a

17-18 Spring-Summer VEWH 800 800 74

19-20 Spring VEWH 878 878 74

Initial environmental watering was an ‘emergency response’ to assist the vegetation during the

prolonged dry conditions which had resulted in a decline in River Red Gum health. The environmental

watering flooded the whole of Carina Bend wetland, but it did not reach the broader floodplain. It was

effective in improving the health of trees lining the creeks and wetlands in the target area, and had the

added benefit of providing some drought refuge for waterbirds. Along with increased foliage vigour, it

was reported that many of the larger River Red Gum and Black Box have since flowered and seeded

with the bands of young seedlings now forming in and around the wetted-up margins. Wetland plants

such as Moira Grass (Pseudoraphis spinescens), Spike Sedge (Eleocharis microcarpa), Marsh

Clubrush (Bolboschoenus medianus) were present. Floodplain fauna that benefited from the watering

events include frogs, turtles and invertebrates (Sunraysia Environmental, 2008).


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4 Water dependent values

Wetlands and waterways on the floodplain are a vital component of the landscape. The habitat

provided by vegetation communities around wetlands is essential to a range of fauna. Other

ecological functions provided by floodplain complexes include water filtration, slowing surface water

flow to reduce soil erosion, flood mitigation and reducing nutrient input into waterways. Protecting the

ecological functioning of wetlands ensures these services are maintained.

Carina Bend provides a range of shelter and food resources for indigenous fauna, flora and

vegetation communities. The types of habitat provided, and consequently the species that utilise the

site, change as water fills the wetlands and floodplain and recedes again.

Flora and fauna data for the site is very limited. While data from the Victorian Biodiversity Atlas

(DELWP, 2016b) and previous site studies (GHD, 2010) have been referenced, it is recommended

that flora and fauna surveys are undertaken at the site to improve knowledge of the site’s ecological

values.

4.1 Environmental values

Listings and significance

Fauna

Forty-nine fauna species have been recorded at Carina Bend, three of which are introduced. Of

special interest and management responsibility are the five water dependent fauna species listed in

legislation, agreements or conventions.

Carina Bend supports species listed under the Commonwealth Environment Protection and

Biodiversity Conservation Act (EPBC Act), Victoria’s Flora and Fauna Guarantee Act (FFG Act), and

the Advisory List of Threatened Fauna in Victoria (VROT advisory list) (Table 6). A full list of fauna

recorded at the site is presented in Appendix 1.

Despite only a limited number of listed fauna being identified in VBA records, it is fair to assume that

more listed species are likely to occur due to the availability of habitat and nearby sightings.

Table 6 - Listed water dependent fauna recorded at Carina Bend

Common name

Scientific name

Type

International agreements

EPBC threatened fauna status

FFG status

VROT advisory list status

White-browed Treecreeper*

Climacteris affinis B - - Listed Vulnerable

Brown Treecreeper*

(SE ssp.)

Climacteris picumnus victoriae

B

-

-

-

Near threatened

Hooded Robin* Melanodryas cucullata cucullata

B - - Listed Near threatened

Carpet Python* Morelia spilota metcalfei

R - - Listed Endangered

Regent Parrot*

Polytelis anthopeplus monarchoides

B

-

Vulnerable

Listed

Vulnerable

Legend: Lifeform type: Amphibian, Bird, Fish, Invertebrate, Reptile, Mammal *Species are included as water dependent due to habitat requirements


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All five listed water dependent species at the site are considered indirectly water dependent due to

habitat requirements (e.g. dependent on nesting hollows in riparian trees).

The White-browed Treecreeper (Climacteris affinis) feeds on insects and invertebrates on the rough

bark of living or dead trees and amongst logs and leaf litter on the ground in forests and woodlands.

They are considered vulnerable in Victoria with populations declining due to habitat loss,

fragmentation and degradation (GHD, 2010).

The Brown Tree-creeper (south-eastern spp.) (Climacteris picumnus victoriae) forages for insects on

tree trunks and amongst fallen woody debris on the ground. The majority of their diet is comprised of

ants, but also includes other insects such as spiders, moths and larvae as well as sap. Hollows in

trees (dead or alive) or tree stumps are essential for nest sites (Office of Environment & Heritage,

n.d.). Appropriate inundation regimes will support a healthy and productive forest ecosystem and

continued supply of habitat resources such as food, hollows and woody debris.

The Hooded Robin (Melanodryas cucullata cucullata) forages on tree trunks, on the ground and in the

air, consuming invertebrates, small lizards and frogs and seeds. The amount of tree and shrub cover,

woody debris and leaf litter is a key factor in species habitat preference and survival (Office of

Environment & Heritage, n.d.).

The Regent Parrot (Polytelis anthopeplus monarchoides) is listed as nationally vulnerable under the

EPBC Act, with estimates of only 2,900 birds left in the wild. This species has quite specific habitat

requirements. It breeds almost exclusively in River Red Gum (Eucalyptus camaldulensis) forest and

woodland, typically nesting in large, old and healthy hollow-bearing trees close to water (Figure 7).

They require trees that are a minimum of 160 years old (Baker-Gabb and Hurley, 2011). Regent

Parrots have also been known to breed in Black Box (Eucalyptus largiflorens). They mostly feed in

large blocks of intact Mallee woodlands usually within 5-10km (maximum 20km) of nest sites, but also

consume flower buds of River Red Gum, Black Box and Buloke (Allocasuarina leuhmanii) (Baker-

Gabb and Hurley, 2011). Regent Parrots are reluctant to fly through open areas and require corridors

of vegetation between nesting and foraging sites.


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Figure 7 - Large River Red Gum provide nesting hollows and habitat for birds such as the Regent Parrot

and Carpet Python (February 2016)

Carpet Pythons rely on habitat provided by River Red Gum forests along major watercourses and

benefit from the vertebrate prey species that live in productive wetlands and floodplains. Trees and

logs with large hollows, or large rock outcrops, plus thick litter or shrub cover close to (within 100m of)

riparian zones, are essential to the existence of Carpet Pythons. Black Box woodlands with hollows

further away from waterways are often used for hibernation (Robertson and Hurley, 2001; DSE,

2003).

Major threats to the Carpet Python habitat include the removal of fallen timber for firewood collection,

fox predation, timber harvesting, grazing and rabbit warren fumigation (as Carpet Pythons are known

to shelter in rabbit warrens) (Robertson and Hurley, 2001).

Vegetation communities

Eleven Ecological Vegetation Classes (EVCs) and one EVC complex are modelled as present within

the target area.


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Table 7 provides a list of these EVCs, along with their bioregional conservation status, Figure 8 displays the spatial arrangement of the EVCs, and Appendix 2 provides detailed descriptions of the EVCs. Table 7 - Ecological Vegetation Classes modelled as present within the Carina Bend target area

EVC no.

EVC name

Area modelled as present within target area (ha)

Bioregional conservation status

98 Semi-arid Chenopod Woodland 0.2 Vulnerable

103 Riverine Chenopod Woodland 0.2 Depleted

104 Lignum Swamp 2.0 Vulnerable

106 Grassy Riverine Forest 0.9 Depleted

Grassy Riverine Forest/Floodway Pond Herbland Complex

30.7

200 Shallow Freshwater Marsh 4.0 Vulnerable

295 Riverine Grassy Woodland 0.1 Depleted

808 Lignum Shrubland 0.4 Least concern

810 Floodway Pond Herbland 40.8 Depleted

813 Intermittent Swampy Woodland 42.9 Depleted

818 Shrubby Riverine Woodland 1.9 Least concern

823 Lignum Swampy Woodland 11.8 Depleted


26

Figure 8 - Ecological Vegetation Classes present in the Carina Bend target area

Low meander scrolls on the floodplain adjacent to the Murray support vegetation communities

dominated by River Red Gum such as Grassy Riverine Forest (EVC 106) and Intermittent Swampy

Woodland (EVC 813) (Ecological Associates, 2007b). At its northern end, Carina Bend Wetland

spreads out into areas of shallow water and sandy benches, supporting Grassy Riverine

Forest/Floodway Pond Herbland Complex and then (slightly higher up) Intermittent Swampy

Woodland on the floodplain.


27

Grassy Riverine Forest is a River Red Gum forest to 25m tall with an understorey of Eumong (Acacia

stenophylla), Tangled Lignum (Muehlenbeckia florulenta) and a range of tussock grasses and

occasional tall shrubs (Figure 9).

Figure 9 - Riverine Grassy Forest in the flow path that feeds wetland #12174 from the north (February

2016)

Intermittent Swampy Woodland is comprised of an overstorey of River Red Gum and Black Box to

roughly 15m tall, with an understorey of Eumong, scattered shrubs such as Tangled Lignum and a

range of grasses and sedges. With frequent inundation it is dominated by flood stimulated species in

association with inundation-tolerant flora (Figure 10 and Figure 11).

Figure 10 – Intermittent Swampy Woodland in the drainage line that connects Carina Bend Wetland to the

Murray River in the south (February 2016)

Ideal flooding for River Red Gum recruitment is late spring to early summer (Johns and et al., 2009),

while ideal flood timing for River Red Gum maintenance and survival is winter to spring following the

natural flooding pattern (Dalton, 1990).

Higher terraces on the central floodplain support Black Box woodlands and Lignum wetlands

(Ecological Associates, 2007c). Black Box provides essential habitat and foraging opportunities for a

range of species including mammals and reptiles and supports a high proportion of ground foraging

and hollow-nesting birds. Black Box can tolerate a range of moisture and salinity conditions (Roberts

and Marston, 2011), however recruitment and establishment is linked to the elevated and continued


28

soil moisture associated with flood events. Under extended periods of dry conditions Black Box is

likely to decline and eventually die (Ecological Associates, 2007a).

Figure 11 - Intermittent Swampy Woodland is present on the terraces above Carina Bend Wetland

(February 2016)

Lignum Swampy Woodland (EVC 823) and Lignum Swamp (EVC 104) are present on terraces

adjacent to Carina Bend Wetland. Lignum Swampy Woodland has an overstorey of 15m tall Black

Box and River Red Gum and an understorey dominated by Lignum, along with Eumong and a mix

of chenopod shrubs, grasses and sedges that can survive extended dry periods. Lignum Swamp

is typically treeless, subject to only infrequent inundation and dominated by Lignum, with a range

of chenopod shrubs, herbs and grasses.

During and after inundation, the bed of Carina Bend Wetland will host Floodway Pond Herbland (EVC

810) (Figure 12). Floodway Pond Herbland is up to 30cm tall, has a large component of ephemeral

grass, sedge and herb species, and is associated with floodway systems with a regular wetting and

drying cycle.


29

Figure 12 - Carina Bend Wetland's wide flat channels are lined with River Red Gum dominated

Intermittent Swampy Woodland. During and after inundation, Floodway Pond Herbland would be present

within the channel bed, currently in a dry phase (February 2016)

Flora

Twenty-five species of flora have been recorded at Carina Bend (a full list of flora can be found in

Appendix 3). None of these are listed under the FFG Act and/or the Advisory List of Rare or

Threatened Flora in Victoria. Seven introduced flora species have also been recorded at the site. It is

likely that a larger range of flora are present at the site but that flora surveys have been limited to

date.

Other fauna

Waterbirds

Waterbird diversity and abundance are influenced by wetland habitat diversity, with different species

and feeding guilds using different habitats for breeding and foraging (Haig, Mehlman and Oring,

1998). Water depth in particular influences waterbird diversity due to the specific feeding behaviours

of different species (Bancroft, Gawlick and Rutchey, 2002). Managing wetlands to provide diverse

habitats such as variable water depth, mud flats, inundated vegetation and areas of deep water

increases the likelihood of waterbird diversity (Taft, Colwell, Isola and Safran, 2002).

Recommendations within this EWMP will be directed toward providing the habitat through a watering

regime appropriate to providing key habitat needs of the waterbird guilds listed in Table 8. This is

based on the habitat types available at the site.

Table 8 - Waterbird functional feeding groups (Roshier, Robertston and Kingsford, 2002) and their

resource use

Waterbird Group

Food Resource

Habitat Use

Waterbird Group

Grazing Waterfowl (e.g. Australian Wood Duck)

Plant material, seeds, invertebrates

Shallow Water, littoral zone

Colonial or solitary

Shoreline Foragers (e.g. Lapwings, Hens)

Plant material, seeds, invertebrates,

Littoral zone, mudflats

Solitary or small groups


30

Providing appropriate water requirements to support the vegetation communities will support habitat

for birds that have adapted to the required flooding and drying cycle (Scott, 1997). With an

appropriate water regime, waterbirds will utilise areas of shallow water, mudflats and the littoral zone

in floodplain channels and wetlands.

Wetland depletion and rarity

The conservation significance of Victorian wetland types has been determined by comparing the

estimated extent prior to European settlement with the remaining extent.

Carina Bend contains three wetland types under the Corrick classification:

• Permanent Open Freshwater,

• Shallow Freshwater Marsh and

• Deep Freshwater Marsh.

Since European settlement, Permanent Open Freshwater has suffered a slight loss across the state

(-6%) and has gained area in Mallee CMA (+5%), possibly due to raised weir levels along the Murray

River permanently inundating wetlands that would previously have been only inundated seasonally.

Within the Robinvale Plains Bioregion it has reduced in extent (-1%). Shallow Freshwater Marsh

and Deep Freshwater Marsh have declined to a much greater extent across the state, (-60% and

-70% respectively); within the Mallee CMA (-6% and -45% respectively) and within the Robinvale

Plains Bioregion (-4% and -37% respectively) (Table 9).

Table 9 – Regional changes in the area of the wetland type (Corrick classification) represented within the

Carina Bend target area. Source: (Mallee CMA, 2006; DELWP, 2016a)

Percentage change in wetland area from 1788 to 1994

Corrick category

Wetland name Total area (ha)

Change in

Robinvale Change

in Change

in Victoria Mallee

CMA Plains

bioregion

Permanent Open Freshwater

Carina Bend wetland (part)

25.6 ha -6%

+5%

-1%

Unnamed 10.9 ha

Shallow wetland #12170

Freshwater -60% -6% -4% Marsh Carina Bend

wetland (part) 11.7 ha

Unnamed 8.5 ha

Deep wetland #12174

Freshwater -70% -45% -37% Marsh Carina Bend

wetland (part) 14.4 ha


31

Ecosystem functions

Wetland ecosystems support distinctive communities of plants and animals and support numerous

ecosystem functions. Floodplain wetlands perform important functions necessary to maintain the

hydrological, physical and ecological health of river systems.

Three key broad ecosystem functions have been identified for the Carina Bend EWMP. Each function

is interlinked and must be supported in order for the ecosystem to flourish. The functions are briefly

described below.

Connections across floodplains, adjacent wetlands and billabongs (lateral)

Inundating the length of Carina Bend Wetland will provide a range of habitat types: deep pools,

shallow benches for macrophyte beds and flooded areas of lignum. During drawdown the wetland will

separate into pools joined by Floodway Pond Herbland and mud flats.

Water levels that engage flood channels, wetlands and floodplain surfaces will promote nutrient and

carbon cycling and return organic material to the river for further processing (Robertston, Bacon and

Heagney, 2001a).

Waterbird groups also access a variety of habitat types such as mud flats, flooded lignum and shallow

aquatic vegetation which only become available following inundation.

Diversity of habitat for feeding, breeding and nursery

Wetland filling and water recession will increase the extent and species diversity of the band of

sedges, rushes and semi-aquatic forbs surrounding wetlands and areas of deeper, semi-permanent

water will support submerged aquatic macrophytes. This inundation cycle will promote high levels of

aquatic productivity and increased habitat complexity for frogs, small native fish, and waterbirds.

When flooded, the ephemeral flora component of Lignum Swampy Woodland and Lignum Swamp will

germinate or expand, providing habitat for frogs, aquatic invertebrates and small native fish and the

water birds that prey on these species. Fringing macrophytes will provide a source of food, refuge

from predators and nesting sites and materials (Kingsford and Norman, 2002).

River Red Gum and Black Box within or adjacent to inundated areas will have increased growth and

vigour, ensuring that they can continue to provide hollows for nesting, perch sites, input of leaves and

coarse woody debris into the wetlands and floodplain.

Transportation and dilution of nutrients and organic matter and increase in macroinvertebrate

productivity and biofilm diversity

Wetland inundation will transport nutrients and carbon into the water column, which will become

available for consumption by bacteria, algae, macrophytes and macroinvertebrates.

Drying of wetlands, particularly during summer and autumn, exposes sediments and facilitates

decomposition and processing of organic matter. The microbial decay of plant material is an important

route for energy and nutrients to enter the food chain (Young, 2001).

Fluctuations in water levels allow exposure of substrates such as large wood and plant stems through a

drying cycle, supporting a mosaic of biofilm species that offer a range of food resources for

macroinvertebrates and fish. Macroinvertebrates with an adult, terrestrial life stage will provide a food

source for insectivorous woodland birds.


32

4.2 Social values

Cultural value

The Mallee region has been occupied for thousands of generations by indigenous people with human

activity dated as far back as 23,400 years ago. The region’s rich and diverse indigenous heritage has

been formed through the historical and spiritual significance of sites associated with this habitation;

together with the strong connection traditional owners continue to have with Mallee’s natural

landscapes.

Given the semi-arid climate of the region, ready access to more permanent water has been a major

determinant of human habitation, and as such the highest densities of identified indigenous cultural

heritage sites are located around or close to areas of freshwater sources.

Within the Mallee CMA region, the Murray River and its associated waterways were important

habitation areas for multiple Aboriginal groups, containing many places of spiritual significance. The

high number of indigenous cultural heritage sites throughout the Murray floodplain is unique in

Victoria, for concentration and diversity. They include large numbers of burial and hunting sites and

middens.

In the south of the region, waterways were focal points for the region’s traditional owners, with many

lakes being the site for large gatherings of social clan groups that afforded trade and cultural exchanges.

Waterways also play a large role in the region’s more recent non-indigenous heritage due to the

historical infrastructure (e.g. buildings, irrigation and river navigation structures) they often contain.

These places provide links to early industries and settlements and play a key part in the region’s

identity.

Cultural heritage

Carina Bend Wetlands are an important indigenous cultural heritage site and contain burial sites,

middens and ovens. Indigenous representation for Carina Bend includes the Robinvale Claimant

Group, Tati Tati and Latji Latji (DSE, 2012), however currently there is no Registered Aboriginal Party

(RAP) for the area nor any applications for RAP status (DPC, 2016).

A historical pumping station is also present at Carina Bend and is covered by a Heritage Overlay

under the Swan Hill planning scheme.

4.3 Recreation

Carina Bend provides opportunities for nature-based recreation for residents of Robinvale, 25km

away. Recreation opportunities include walking, trail bike riding, four wheeling driving, picnicking,

camping, fishing and swimming. VEAC recommendations (2008) continue to allow camping and

campfires in the area.

4.4 Economic values

Carina Bend has previously been used for grazing and firewood collection. Surrounding land uses

include irrigated agriculture (almonds, grapes and oranges) and dryland cropping.

4.5 Significance

Carina Bend supports populations of the listed Regent Parrot, Brown Tree-creeper and White-browed

Tree-creeper and Carpet Python. These species rely on the health of large mature River Red Gums,

which are prevalent with the target area. Carina Bend wetland is 5 km long providing a significant

wetland habitat off the Murray when inundated. The wetland can provide excellent seasonal habitat

for fish, frogs and waterfowl.


33

5 Ecological condition and threats

5.1 Current condition

The condition of wetlands at Carina Bend has not been assessed using the state-wide Index of

Wetland Condition. The condition information described below is based on brief field observations and

limited existing literature. It should be considered a high priority to undertake a condition assessment

of wetlands at Carina Bend using the Index of Wetland Condition.

Field inspections undertaken in December 2019 found wetlands at Carina Bend to be in a

drawdown phase following a spring water delivery. Healthy mature River Red Gums line the Murray

River frontage and Carina Bend Wetland and new recruitment was observed within the wetland

(Figures 13a/b). Aquatic grass (Moira spp. nc) was also seen growing along the margins of the

inundated area (Figure 14). In contrast, River Red Gum on high terraces outside the main Carina

Bend Wetland channel continue to show evidence of poorer health. Continuation of watering at

Carina Bend wetland will result in improved tree health for significant areas of River Red Gums

along the considerable length of the wetland channel.

Figure 13a – Healthy mature River Red Gum line the edges of Carina Bend Wetland. (December 2019)


34

Figure 13b – River Red Gum recruitment is occurring within the wetland bed (below). (December 2019)

Figure 14 – Aquatic grass (Moira spp. n.c.) growing along the margins of the inundated area of Carina

Bend Wetland (December 2019)


35

5.2 Water related threats

The Aquatic Value Identification and Risk Assessment (AVIRA) database is an on-line tool used by

Victorian waterway managers to store data about the values, threats and risks to waterway health in

their region. The database evaluates threats for a range of sub-indices including water regime,

invasive fauna and acid sulphate soils (Peters, 2009).

Invasive fauna aquatic

Although no aquatic species records are available for the site, wetlands on site are likely to support

Common Carp (Cyprinus carpio). Carp have been found to contribute to the loss of aquatic vegetation

and increased turbidity, degrading the habitat for waterfowl (Purdey and Loyn, 2008) and native fish.

Common Carp also competes with the native fish for habitat and food (Mallee CMA, 2003).

Invasive fauna terrestrial

Introduced species recorded at the site include Red Fox (Vulpes vulpes) and Common Starling

(Sturnus vulgaris). European Rabbit (Oryctolagus cuniculus) and Cat (Felis catus) are also likely to be

present.

Foxes and Cats predate on native birds and mammals and both are listed as potentially

threatening processes under the Flora and Fauna Guarantee Act 1988 (DSE, 2002, 2004a).

Foxes are known to predate on young Hooded Robins (NSW Scientific Committee, 2008)

and on Carpet Pythons (Robertson and Hurley, 2001).

Rabbits can over-browse flora species and reduce survival and recruitment success, cause erosion,

compete with native herbivores for food and burrows and support high populations of introduced

predators such as foxes and cats (Office of Environment & Heritage, 2015). Fumigation of Rabbit

warrens has been known to cause the death of Carpet Pythons as they occasionally use warrens for

shelter (Robertson and Hurley, 2001).

Invasive flora wetland

Agricultural and other weeds are an ongoing threat on the Murray River floodplain and have been

recorded at Carina Bend. A full list of introduced flora is presented in Appendix 3.

Overland flow is occurring from privately held irrigation land within the WMU sub-unit. These flows

could act as a vector for weed propagules and favour weed species by increasing nutrient levels at

the site.

An irrigation channel located on private land at Carina Bend is completely choked by Cumbungi

(Typha sp.) due to stable shallow flooding during summer.

Changed water regime

As discussed in the hydrology section of this EWMP, the hydrology of the target area has been

greatly impacted by the regulation of the Murray River. The proposed water regime assessment takes

into account the impacts of regulation of the primary water source of the wetland (Murray River), other

activities which may impact the wetland water regimes, impacts to seasonality, duration and

frequency of the water regime and the severity of the effects of these activities.


36

6 Management objectives

6.1 Management goal

The management goal for Carina Bend is:

“To provide a water regime that will support the health of fringing mature River Red Gum and provide

seasonal habitat for native fish, frogs and waterfowl.”

6.2 Ecological objectives

Ecological objectives represent the desired ecological outcomes of the site based on the

management goal which has been framed around the key values outlined in the Water Dependent

Values section of this EWMP. In line with policy in the Victorian Waterway Management Strategy

(VWMS) the ecological objectives are expressed as the target condition or functionality of each key

value.

The ecological objectives for Carina Bend Wetland are:

Carina Bend wetland

• Support the health of mature River Red Gum trees along the wetland perimeter

• Provide seasonal aquatic habitat that supports a diverse population of native fish and

frogs

• Reliable nesting and feeding habitat for waterfowl in winter and spring

• Healthy Lignum vegetation that provides productive habitat for small fish and frogs

when flooded and shelter and foraging habitat for terrestrial fauna when dry


37

Table 10 - Ecological objectives for Carina Bend

Ecological objective

Justification

Support the health of mature

River Red Gum trees along the

wetland perimeter

Mature River Red Gum provides nesting hollows and roosting sites for the

Regent Parrot, Brown Tree-creeper, White-browed Tree-creeper and

Carpet Python which are all listed species found within the target area.

Provide seasonal aquatic habitat

that supports a diverse

population of native fish and

frogs

As well as the intrinsic value of native fish presence, small- bodied

native fish also provide an important food source for piscivorous

waterbirds and some large-bodied native fish species.

Reliable nesting and feeding

habitat for waterfowl in winter and

spring

Waterfowl nest in reed beds and flooded Lignum or River Red Gum

through winter and spring.

Waterfowl will use the littoral zone and shallow water areas of Carina

Bend wetland for feeding as the water levels recede through late

summer/autumn.

Diverse macrophyte and frog

population supported by healthy

Lignum Swampy Woodland

vegetation

Inundation of Lignum woodlands will allow colonisation by native fish

including Gudgeon and Murray-Darling Rainbowfish. Shelter and feeding

habitat for frogs will also expand from the fringing wetland areas to the

refuge of the deeper wetland areas.

Healthy Lignum can also provide shelter and feeding sites for Carpet

Python and Woodland birds such as Brown Tree- creeper.

6.3 Hydrological objectives

Hydrological objectives describe the components of the water regime required to achieve the

ecological objectives for the target area. The hydrological requirements to achieve each of the

ecological objectives are presented in Table 11 and described below.

River Red Gum woodlands require flooding every two to four years with durations of two to four

months. Flood events may differ and a variation in ponding duration around the mean requirement for

this species is encouraged. Although the timing of flooding is not vital for River Red Gum, spring-

summer flooding encourages greater growth. Timing is however important for understorey plant

communities – flooding in spring encourages a diversity of emergent macrophytes while flooding in

summer tends to promote Common Reed and Cumbungi. The critical interval for River Red Gum

woodland inundation is five to seven years to prevent deterioration of tree condition (Roberts and

Marston, 2011).

Lignum can tolerate a wide range of wet and dry conditions as well as moderate salinity levels.

Frequencies of one to three years are needed to maintain large shrubs with vigorous canopy while

flooding every three to five years for maintenance of healthy shrubs. Intervals of seven to ten years

can be tolerated by small shrubs but these are not suitable as nesting platforms. Durations of three to

seven months sustain vigorous canopy, but waterlogging is detrimental. Although the timing of

flooding is not crucial for Lignum, following natural seasonality is encouraged to provide for

understorey and wetland plants (Roberts and Marston, 2011).

Flooding of wetland and floodplain vegetation in spring and summer provides a source of food, refuge

and nesting sites and materials for waterbirds (Kingsford and Norman, 2002).


38

Hydrological objectives for Carina Bend are presented in Table 11.

Table 11- Hydrological objectives for Carina Bend

Level

Zone

Frequency

Duration

Timing

44.7

Expose wetland bed

1:1

1-6

Late summer/early autumn

45.5

Littoral zone

1:1

4-6 months

Late winter/early summer

46

Fringing River Red Gum

1:2

2-4 months

Late winter/early spring

46.7

Lignum wetlands

1:4

3-7 months

Early spring/late summer

6.4 Watering regime

The wetland watering regime has been derived from the ecological and hydrological objectives. To

allow for adaptive and integrated management, the hydrological objectives have been framed using

the seasonally adaptive approach. This means that a watering regime is identified for optimal

conditions, as well as the maximum and minimum tolerable watering scenarios. The minimum

watering regime is likely to be provided in drought or dry years, the optimum watering regime in

average conditions and the maximum watering regime in wet or flood years.

The optimal watering regime is described below. Due to the inter-annual variability of these estimates

(particularly the climatic conditions), determination of the predicted volume requirements in any given

year will need to be undertaken by the environmental water manager when watering is planned.

The watering regime has been derived following review of the pre-regulation hydrology data.

Optimal watering regime

The optimal watering regime is to maintain Carina Bend Wetland as a semi-permanent freshwater

wetland, with a seasonally inundated fringe. Fill Carina Bend Wetland every second year in late

winter/early spring to 46m AHD, with water levels falling naturally by seepage and evaporation

over summer and autumn. In every fourth year, fill wetland to 46.7m AHD to inundate the Lignum

communities in September, with water levels falling naturally by seepage and evaporation over

summer and autumn.

Minimum watering regime

Fill Carina Bend Wetland every second year to 46m AHD to maintain fringing River Red Gum health,

with water levels falling naturally by seepage and evaporation over summer and autumn to expose

the wetland bed.

Maximum watering regime

The optimal watering regime is to maintain Carina Bend Wetland as a permanent freshwater wetland,

with a seasonally inundated fringe. Fill Carina Bend Wetland every second year in late winter/early

spring to 46.7m AHD, with water levels falling naturally by seepage and evaporation over summer

and autumn. Top up when water levels fall below 45.5m AHD in summer to maintain inundation of

the littoral zone. In every fourth year allow water levels to fall naturally through seepage and

evaporation over summer and autumn, allowing exposure of the wetland bed.


42

7 Managing risks to achieving objectives

Threat

Likelihood

Consequence

Risk – H, M, L

(likelihood x

consequence)

Management measure

Residual

risk

Failure to meet ecological objectives

Possible

High

H

Monitoring program in place. Adaptive approach.

L

Species, communities or ecological functions have

been overlooked in water regime due to lack of data

Possible

High

H

Review ecological survey results and update

objectives if significant gaps are found.

L

Inundation duration too long or too short

Possible

High

H

Monitoring program in place. Adaptive approach

as additional baseline and monitoring outcome

data is available.

L

Flooding of private land

Possible

Moderate

M

Observe long range weather forecasts, monitor

Murray River flows, and manage delivery.

Communication in place with private landholders.

L

Criminal damage or theft of water delivery

infrastructure

Possible

Moderate

M

Utilise appropriate security devices on equipment

and proactively engage with the community prior to

watering event to gain support for the program.

L

Damage to infrastructure, particularly pumps or

regulators leading to loss of water from target area

Likely

Moderate

M

Appropriate engagement and site management in

place. Regular monitoring and staff presence

during watering events.

L


43

Threat

Likelihood

Consequence

Risk – H, M, L

(likelihood x

consequence)

Management measure

Residual

risk

Maintenance required to delivery infrastructure

(pump/channel etc.) during proposed watering event

Likely

High

VH

Include maintenance of channel on annual

inspection checklist. Ensure pump contractors are

appropriately qualified and have appropriate

quality assurance processes in place.

L

Monitoring program is unable to detect improvement

in short to medium term

Possible

High

H

Engagement with key stakeholders confirming

expected outcomes, timeframes and assumptions.

L

Damage to cultural heritage sites through

construction of temporary infrastructure and

equipment

Possible

High

H

Site risk assessments undertaken and mitigations

in place prior to any works occurring. Cultural

Heritage Management Plans in place.

L


44

8 Environmental water delivery infrastructure

8.1 Constraints

The infrastructure to allow inundation of the target area needs to be planned and implemented. Carina

Bend is currently able to be watered to a level of 44.8m AHD. The area that is able to be inundated

without the proposed infrastructure is shown in Figure 16. Full inundation of the target area is not

possible without the infrastructure and works recommendations listed below.


45

Figure 16 - Current inundation extent without proposed infrastructure

In addition to infrastructure requirements to enable delivery of environmental water, access roads

must be maintained to ensure continued access to the target area by management vehicles and

visitors.

8.2 Infrastructure or complementary works recommendations

It is recommended that track raising is undertaken in three locations, as shown in Figure 16. The road

raising ensures that environmental water pumped into the Carina Bend Wetland is not unintentionally

lost back to the river via the floodplain channels. Conceptual designs would need to be developed to

confirm the works required to implement the recommendations in this plan. Cultural heritage

investigations would be required. Filling of the wetland would be undertaken using a temporary pump

located near the road raising at river km 1082.


46

10 Demonstrating outcomes

10.1 Monitoring priorities at the site

The following priorities for monitoring have been identified for the Carina Bend target area:

• IWC monitoring should be undertaken at Carina Bend Wetland and wetlands #12174

and #12170 on a five-yearly basis.

• Photo point monitoring of tree health within the woodlands should be undertaken.


47

11 Consultation

This Plan was developed in collaboration with key stakeholders namely Parks Victoria, the

Department of Environment, Land, Water and Planning, and local interest groups.

Table 12 - Consultation for development of Carina Bend EWMP

Meeting Date

Stakeholders

Details

Sept 2012

Parks Victoria

Present initial concept and

contents of draft plan and seek

feedback October 2012


May 2016

Parks Victoria

Presentation of plan

June 2016



June 2016

Mildura BirdLife


June 2016

Murray Lower Darling Rivers Indigenous Nations


June 2016

Department of Environment Land Water and

Planning



48

12 Knowledge gaps and recommendations

Concept design report for infrastructure

A concept design report is required to scope the infrastructure requirements at three sites at Carina

Bend. It is likely that that road raising will be required, although a single regulator at river km 1082

should also be investigated.

Index of Wetland Condition assessment

The target area wetlands should be incorporated into the five-yearly Index of Wetland Condition

assessments.


49

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GHD, 2010. Survey of White-browed Treecreeper at Pink Lakes and Wemen Flora and Fauna Reserve. Mildura, Victoria: Mallee CMA.

Gippel, C.J., 2014. Spells analysis of modelled flow for the River Murray from Swan Hill to the South Australian Border. Stockton: Fluvial Systems Pty Ltd, Stockton. Mallee CMA, November.

Haig, S., Mehlman, D. and Oring, L., 1998. Avian movements and wetland connectivity in landscape conservation. Conservation Biology, 12(4), pp.749–758.

Johns, C. and et al., 2009. Literature review and experiemental design to address retaining floodwater on floodplains and flow enhancement hypotheses relevant to native tree species. Wodonga: Murray-Darling Freshwater Reseach Centre.

Kingsford, R.T. and Norman, F.I., 2002. Australian waterbirds - products of the continent’s ecology. Emu, (102), pp.47–69.

http://www.environment.gov.au/webgis-framework/apps/pmst/pmst.jsfhttp://mapshare2.dse.vic.gov.au/MapShare2EXT/imf.jsp?site=bimhttp://www.depi.vic.gov.au/conservation-and-environment/victorias-http://www.dpc.vic.gov.au/index.php/aboriginal-affairs/registered-aboriginal-parties


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LCC, 1989. Mallee Area Review Final Recommendations. Melbourne, Victoria: Land Conservation Council.

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Abbreviations and acronyms

CMAs Catchment Management Authorities

DELWP Department of Environment, Land, Water and Planning

EVC Ecological Vegetation Class

EWMP Environmental Water Management Plan

FSL Full Supply Level

MDBA Murray-Darling Basin Authority (formally Murray-Darling Basin Commission, MDBC)

TSL Targeted Supply Level

VEWH Victorian Environmental Water Holder


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Appendix 1 – Fauna species list

Common name Scientific name Type

Yellow-rumped Thornbill Acanthiza chrysorrhoa B

Grey Teal Anas gracilis B

Pacific Black Duck Anas superciliosa B

Southern Whiteface Aphelocephala leucopsis B

Dusky Woodswallow Artamus cyanopterus B

Sulphur-crested Cockatoo Cacatua galerita B

Little Corella Cacatua sanguinea B

Australian Wood Duck Chenonetta jubata B

Horsfield's Bronze-Cuckoo Chrysococcyx basalis B

White-browed Treecreeper Climacteris affinis B

Brown Treecreeper (south-eastern ssp.) Climacteris picumnus victoriae B

Grey Shrike-thrush Colluricincla harmonica B

White-winged Chough Corcorax melanorhamphos B

Australian Raven Corvus coronoides B

Little Raven Corvus mellori B

Laughing Kookaburra Dacelo novaeguineae B

Varied Sittella Daphoenositta chrysoptera B

White-faced Heron Egretta novaehollandiae B

Black-fronted Dotterel Elseyornis melanops B

Galah Eolophus roseicapilla B

Eurasian Coot Fulica atra B

Peaceful Dove Geopelia striata B

Magpie-lark Grallina cyanoleuca B

Australian Magpie Gymnorhina tibicen B

White-plumed Honeyeater Lichenostomus penicillatus B

Variegated Fairy-wren Malurus lamberti B

Splendid Fairy-wren Malurus splendens B

Noisy Miner Manorina melanocephala B

Hooded Robin Melanodryas cucullata cucullata B

Rufous Whistler Pachycephala rufiventris B


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Common name Scientific name Type

Striated Pardalote Pardalotus striatus B

Australian Pelican Pelecanus conspicillatus B

Welcome Swallow Petrochelidon neoxena B

Tree Martin Petrochelidon nigricans B

Red-capped Robin Petroica goodenovii B

Little Black Cormorant Phalacrocorax sulcirostris B

Little Friarbird Philemon citreogularis B

Yellow Rosella Platycercus elegans flaveolus B

Regent Parrot Polytelis anthopeplus monarchoides B

Red-rumped Parrot Psephotus haematonotus B

Willie Wagtail Rhipidura leucophrys B

Apostlebird Struthidea cinerea B

Common Starling* Sturnus vulgaris B

Australasian Grebe Tachybaptus novaehollandiae B

Straw-necked Ibis Threskiornis spinicollis B

Western Grey Kangaroo Macropus fuliginosus M

European Rabbit* Oryctolagus cuniculus M

Red Fox* Vulpes vulpes M

Carpet Python Morelia spilota metcalfei R

*Introduced species Lifeform type: Invertebrate (I), Fish (F), Amphibian (A), Reptile (R), Bird (B), Mammal (M)

Source: (DELWP, 2016b)


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Appendix 2 – Ecological Vegetation Classes

EVC no.

EVC name


Description

98

Semi-arid Chenopod Woodland

Vulnerable

Sparse, low non-eucalypt woodland to 12 m tall of the arid zone with a tall open chenopod shrub-dominated understorey to a treeless, tall chenopod shrubland to 3 m tall. This EVC may occur as either a woodland (typically with a very open structure but tree cover >10%) or a shrubland (tree cover


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EVC no.

EVC name


Description

818

Shrubby Riverine Woodland

Least concern

Eucalypt woodland to open forest to 15 m tall of less flood- prone (riverine) watercourse fringes, principally on levees and higher sections of point-bar deposits. The understorey includes a range of species shared with drier floodplain habitats with a sparse shrub component, ground-layer patchily dominated by various life-forms. A range of large dicot herbs (mostly herbaceous perennial, several with a growth-form approaching that of small shrub) are often conspicuous.

823

Lignum Swampy Woodland

Depleted

Understorey dominated by Lignum, typically of robust character and relatively dense (at least in patches), in association with a low Eucalypt and/or Acacia woodland to 15 m tall. The ground layer includes a component of obligate wetland flora that is able to persist even if dormant over dry periods.

Source: (DELWP, 2016a; DSE, 2004b)


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Appendix 3 – Flora species list

Common name Scientific name

Eumong Acacia stenophylla

Cattle Bush Alectryon oleifolius subsp. canescens

Spear Grass Austrostipa spp.

Belah Casuarina pauper

Spear Thistle* Cirsium vulgare

Couch Cynodon dactylon

Tangled Lignum Duma florulenta

Nodding Saltbush Einadia nutans

River Red-gum Eucalyptus camaldulensis

Black Box Eucalyptus largiflorens

Spurge Euphorbia spp.

Rough Raspwort Haloragis aspera

Smooth Cat's-ear* Hypochaeris glabra

Prickly Lettuce* Lactuca serriola

Poison Pratia Lobelia concolor

Wimmera Rye-grass* Lolium rigidum

Grassland Wood-sorrel Oxalis perennans

Warrego Summer-grass Paspalidium jubiflorum

Prickly Fan-flower Scaevola spinescens

Variable Sida Sida corruga

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